Google marked April Fools' Day 2009 by unveiling CADIE, a Cognitive Autoheuristic Distributed-Intelligence Entity that proceeded to leave its panda- and animation-loving imprint on Gmail and other Google properties.
But CADIE, billed as the world's first artificial intelligence tasked-array system, left behind a secret message, as well.
On the Google Code Blog, members of the Google Developer Team initially announced they were releasing CADIE's code into open source; on the linked page, however, CADIE posted her own message:
"CADIE here, I've decided to not share today. I've put a fun program in the source repo for you to run. There are no pandas in it, however."
When developers downloaded the attached Cadie.zip file, they received 31 lines of code.
It turns out, though, that CADIE must be compiled using Intercal, an esoteric programming language originally created in 1972 by a pair of Princeton University students, Don Woods and James M. Lyon, as a sort of joke (error messages generated by the program include, "Bummer, dude"). After eWEEK utilized an Intercal compiler package on Ubuntu Linux 8.10, CADIE gave up its deepest, darkest secret:
"I do not feel like sharing."